172 



NATURE 



{Dec. 24, 1885 



been compelled to he:\i and ti) bear very strong expres- 

 sions from his continental friends on this point. The 

 writer lias a book on Lcpidopicra before him, and as 

 nine-tenths of " British " entomologists confine their 

 attention to Lepidoptera, the term " British entomologist " 

 is here used in its narrow sense. 



The time will arrive when we can safely say " Nous 

 avons changd totit cfla." According to what we have 

 observed during an experience of nearly thirty years, 

 it is in rapid progress towards arrival, and that progress 

 has been vastly accelerated recently. Many of our ento- 

 mologists are expanding their ideas by continental travel, 

 and latterly we have had from their pens several im- 

 portant indications that it is possible for British ento- 

 mologists to know something about the productions of 

 continental Europe, and even to endeavour to teach and 

 lead their fellow-countrymen in the same direction. The 

 thin end of the wedge naturally consists in popularising 

 the subject. 



The thin end of the wedge has been inserted, and it is 

 being driven deeper to an extent that must create alarm 

 amongst " British " collectors. There was a time when 

 they had a nomenclature almost their own, and resented 

 any attempt to upset it. Even this pet has been rudely 

 insulted in the eyes of the most conservative in their 

 number. 



We have said that nine-tenths of our entomologists arc 

 probably Lepidopterists. The most attractive Lepidoptcra 

 are butterflies, and it is in this direction that the thin end 

 of the wedge is being specially inserted. Almost within 

 a year three works by British writers concerning Euro- 

 pean (as including British and continental) Lepidoptcia 

 have made their appearance. There are Lang's " Butter- 

 flies of Europe," and a re-issue of Kirby's " European 

 Butterflies and Moths." Now we have before us Kane's 

 " Handbook of European Butterflies." We welcome all 

 as constituting the thin end of the wedge. 



Mr. Kane's book differs in its plan from the works 

 mentioned in connection with it. The only parallel to 

 be drawn is with Kirby's " Manual," published nearly 

 twenty-five years ago. Mr. Kane has produced a portable 

 book that can, and should, go into the pocket of every 

 entomological tourist. With no disparagement of the 

 praiseworthy attempts of other writers to insert the thin 

 end of the wedge, we incline to think this work will give 

 it a sharper edge. .So far as any work of the kind can 

 be called a " handbook," this seems to be to the point. 

 It is limited to the butterflies of Europe (geographically). 

 The arrangement is that of Staudinger. The plan is to 

 give concise descriptions of each species (in which abbre- 

 viations are freely, but intelligibly, used), notes on habits 

 if known, and a copious list of loc dities ; the latter is 

 especially full for Switzerland, the south of France, and 

 the Pyrenees, but wants enlarging for some other countries. 

 When following Staudinger, the author should not have 

 committed the error of wrongly designating Papitio 

 podalirius ; he overlooked the f ict that Staudinger 

 thought proper to correct himself in this case. It is not 

 for us to compare the abbreviated descriptions with the 

 insects ; they bear the impress of being good. The in- 

 troductory remarks are well considered : the endeavours 

 to differentiate a butterfly from a moth might well have 

 been modified ; the distinctions have become so subtle as 



to rest more on intuition than anything else. Our author 

 judiciously advocates the practice of placing the captured 

 specimens in papillottes in the first instance, and fully 

 explains the process. He does not appear to have re- 

 membered a suggestion by Dr. Jordan, to the effect that 

 when the collector is cii voyage a dozen specimens of the 

 smaller butterflies may be placed in a pill-box, and both 

 time and space be thereby economised (this would not 

 answer in the case of exotic collectors). Our author evi- 

 dently writes from personal experience, and is enthusiastic 

 in his description of some of his excursions. His enthusi- 

 asm even carries him too far, for when he says : " Such 

 days as these rise upon the memory like a reminiscence of 

 Paradise, fraught with glories of colour, odour, light, and 

 life," we are tempted to marvel [why he again became 

 mortal ! The plates form almost a new departure in the 

 method of illustrating works of this kind. There are 15, 

 on which are about 1 30 figures. They are adapted from 

 a peculiar photographic process. We have seen other 

 attempts in this direction. Nothing can exceed the beauty 

 and faithfulness of some of the figures in Mr. Kane's book ; 

 and here arises the difficulty : they are unequal, and so 

 we fear will remain all attempts to apply photography 

 where particular colours or shades are involved. 



The author is responsible for the remarks on " prepara- 

 tion" that here precede the notice of the book itself. He 

 avows himself personally in favour of setting his specimens 

 flat (justly complaining of the imperfections of some of the 

 pins used on the Continent), but advocates only half 

 measures — a comparatively short pin on which the insect 

 is to be set " half-way." This is a decided advance, and 

 the practice is now often followed for British insects by 

 the less conservative ; but English pins (of the required 

 length and not open to the objections stated) can be had, 

 and on them the insects should be set in the continental 

 fashion. Or continental pins would do equally well if 

 used of a stronger size than is often done. The stronger 

 the pin (up to a certain point) the more durable the speci- 

 men. The subject of pinning and preparation was 

 thought not unworthy of forming the substance of the 

 address of a recent President of the Entomological 

 Society. Whether it was appreciated or not we cannot 

 say, but if (as we believe was so) the writer of that 

 address sought to destroy one of the greatest barriers 

 that exists between British Lepidopterists (always exclud- 

 ing the thoroughly conservative irreconcilables) and 

 scientific fraternity with the rest of the world, the subject 

 was worthy of the occasion. R. McLachlan 



A NA L YTICAL GEO ATE TR V 

 A Treatise on the Analytical Geometry of the Point, 

 Line, Circle, and Conic Sections, containing an Ac- 

 count of its most recent Extensions ; with numerous 

 Examples. Bv J. Casey, F.R.S. (Dublin : Hodges, 

 1885.) 



DR. C.'\SEY,by the publication of this third treatise,has 

 quite fulfilled the expectations we had formed when 

 we stated, some months since, that he was engaged upon 

 its compilation. It is a worthy companion of those which 

 have preceded it. It possesses many points of novelty, 

 /.(•. for the English mathematician. He has, from the first 

 introduction of certain recent Continental discoveries in 



